Quote:
Originally Posted by plnyyanks
sound waves move a magnet surrounded by a coil, producing a current.
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Typically, sound waves move the coil. The magnet is stationary.
By the way, the fact that these two cases had separate physical interpretations was a burr under Einstein's saddle that was a motivating factor for his 1905 paper
On The Electrodynamics of Moving Bodies.
Microphones can also use capacitance (sound waves move a diaphragm which changes its capacitive coupling to a second diaphragm) and the piezoelectric effect (sound waves distort a crystal which creates a voltage).